Fuhrman grading system
The original case series is small by contemporary standards (n=103) and included a composite of a different renal cell carcinoma variants. Survival data was only available for 85 of the cohort (see  for other criticisms of the original methodology).
One problem is that grading assesses nuclear size, nuclear pleomorphism and nucleolar prominence. Where there is discordance between any of these three factors, it is not clear which component should be given priority. This may explain its fair to, at most, moderate inter-observer reproducibility. More recent data suggests that not all of these three factors necessarily correlate with prognosis.
Its utility for the clear cell variant is more compelling, but not completely so, particularly when other factors like stage are taken into account (in studies where multivariate analysis has been performed). It is less reliable for the papillary variant, for which other grading system have been mooted.
|Grade||Nuclear size||Nuclear quality||Nucleoli|
|Grade 1||10 μm||small, round and uniform||absent to inconspicuous|
|Grade 2||15 μm||larger, crinkly nuclear membrane||inconspicuous (visible at x40)|
|Grade 3||20 μm||irregular nuclear membranes||conspicuous (visible at x10)|
|Grade 4||>20 μm||irregular nuclear membrane, pleomorphic, multi-lobed with clumped chromatin; +/- sarcomatoid spindle cells||very prominent|
- ↑ Fuhrman SA, Lasky LC, Limas C. Prognostic significance of morphologic parameters in renal cell carcinoma. The American journal of surgical pathology. 1982 Oct; 6(7):655-63.
- ↑ Delahunt B, Egevad L, Samaratunga H, Martignoni G, Nacey JN, Srigley JR. Gleason and Fuhrman no longer make the grade. Histopathology. 2016 Mar; 68(4):475-81.(Link to article – subscription may be required.)
- ↑ Sika-Paotonu D, Bethwaite PB, McCredie MR, William Jordan T, Delahunt B. Nucleolar grade but not Fuhrman grade is applicable to papillary renal cell carcinoma. The American journal of surgical pathology. 2006 Sep; 30(9):1091-6.(Link to article – subscription may be required.)
- ↑ Delahunt B. Advances and controversies in grading and staging of renal cell carcinoma. Modern pathology : an official journal of the United States and Canadian Academy of Pathology, Inc. 2009 Jun; 22 Suppl 2:S24-36.(Link to article – subscription may be required.)